Remote control system for radio receiving sets



July 18, E H RR TT REMOTE CONTROL SYSTEM FOR RADIO RECEIVING SETS Filed Oct. 5, 1929 2 Sheets-Sheet l INVENTOR.

1 77. Merri tt f6; W. Pk

A TTORNE Y.

E. H. MERRITI' 1,918,857

REMOTE CONTROL SYSTEM FOR RADIO RECEIVING SETS Juiy 18, 1933.

Filed Oct. 5, 1929 2 Sheets-Sheet 2 SET IN VEN TOR.

b $2.; MALL A TTORNE Y.

Patented July 18, 1933 PATENT OFFEKIE EDWARD H. MERRITT, OF FORT WAYNE, INDIANA REMOTE CONTROL SYSTEM FOR RADIO RECEIVING SETS Application filed October 5, 1929.

The invention relates to radio receiving apparatus and it is directed particularly to systems by which to remotely control such apparatus.

5 The object of the invention is to provide novel means by which a radio receiving set may be adjusted at a remote point to tune it with all broadcasting stations within the range of the set and to regulate the volume 10 of the reception.

The invention is illustrated in the accompanying drawings in which Figure 1 is an elevational view of the gang condenser operating mechanism; Fig. 2 a

r plan view of the same; Fig. 3 an elevational view of the volume control operating mechanism; Fig. 1 a plan view of the same; Fig.

5 a view of the remote controlling mecha nisms and of the system partly in diagrammatic form and Fig. 6 a side View of the dialng switch partly in section.

In the illustrative embodiment of the invention, the operating mechanism for the gang condenser 1 is mounted in the radio cabinet and comprises a suitable frame 2 upon which a shaft 3 is supported, the shaft being suitably connected to the rotatable or rocking element 4 of the condenser 1. A gear 5 is secured to the shaft 3 and meshes with. a gear 6 secured to a shaft 7 supported by the frame 2. The ratio of the gears and 6 is such that the shaft 3 will be driven at a selected speed.

A ratchet wheel 8 is secured to the shaft 7 and a spring 9 engages the teeth of the wheel and is supported on the frame 2. A pawl 10 is pivotally mounted in a carrier 11 and is adapted to engage the ratchet wheel 8 under the influence of the spring 12. The carrier 11 is fixed on two rods 13 longitudinally slidably mounted in a support 14 secured to the frame 2. The rods 13 are secured at one end to the armature 15 of the electro-magnet or solenoid 16. A spring 17 is connected to the sliding carrier 11 and to the frame 2. The energization of the elec tro-magnet 16 attracts its armature 15 and causes'the pawl carrier to move toward the magnet and the pawl rotates the ratchet wheel 8 a selected degree. A second ratchet Serial No. 397,466.

wheel 18 is mounted on the shaft 7 and is driven by the pawl 19 mounted on the carrier 20 that is slidably mounted on the rods 21 projecting from the armature 22 of the electro-magnet or solenoid 23. The spring 24 opposes reciprocation of the carrier and the spring 25 maintains engagement of the pawl 19 with the ratchet wheel 18.

An electro-magnet or solenoid 26 is sup ported on the frame 2 and its armature 27 is secured to a rod 28 having a lateral projection 29 thereon that normally engages the lower side of the spring 9. The rod passes through a guide bracket 80. When the magnet 26 is energized the attraction of its armature raises the rod 28 and the projection 29 disengages the spring 9 from the wheel 8, and the ratchet wheels and the several shafts including the member a of the gang condenser 1 return to neutral position, the pawls 10 and 19 being rocked away from the. ratchet-s 8 and 18 by the pins 70, which the pawls abut as the springs 17 and -1 re tract the pawl carriers, this return movement being effected by a coiled spring enclosed within a casing 31 and secured at one end to a sleeve 32 on the shaft 7 and at its other end to the casing. Suitable means is provided for regulating the tension of the spring such as the arm 38 that is attached to the sleeve 32 and by which the sleeve may be rotated to wind or'unwind the spring, a removable stop 84 on the frame 2 being abutted by the arm when the desired adjustment of the spring tension has been made.

There are several types of variable condensers in general use in radio by which to tune the set to the frequency of any station within its range. These condensers in the main differ in the shape or form of their movable plates and this shape determines the eX- tent of angular movement of the plates necessary to secure the required capacity for each change of frequency. Since it is recognized that the higher the frequency the less is the amount of capacity required to secure that frequency, the movements of the movable plates in most variable condensers diminish in extent in a geometrical progression for the higher frequencies and to indicate these movements the scale on the dial of the set is graduated in the same or a corresponding geometrical progression. In some radio sets the graduations on the scale are uniformly spaced and arbitrarily numbered rather than given the kilocycle values. In many sets the scale on the dial begins with 550 kilocycles.

In order that my remote control system shall be capable of use with the several types of radio sets it is essential that the teeth on each of the ratchet wheels 18 and 8 shall be spaced in the same geometrical progression as the scale on the dial of the set to which the system is applied in order to secure the various correct movements of the condenser plates by the rotation of the ratchet wheels. The extent of movement of the armatures of the electro-magnets 16, 2.3 corresponds to the maximum 10 kilocycle movement and the .maximum 100 kilocycle movement of the condenser respectively and it is the same for each excitation of the electro-magnet, hence the teeth on each of the ratchet wheels are spaced so that the uniform movement of the pawls carried by the armatures respectively will move the ratchet wheels the correct distance as prescribed by the dial on the radio set. The teeth on the ratchet wheel 18 are spaced respectively to correspond to 100 kilocycles on the dial ofthe radio set and each tooth is so set that the pawl 19 as it advances from its normal retracted position, will engage the tooth at the correct point in its (the pawls) travel to rotate the ratchet wheel the correct distance, it being clear that when for any frequency the movement of the movable plates of the condenser, as indicated by the dial on the set, is less than that of the normal stroke of the pawl 19, the tooth on the ratchet wheel 18 corresponding to that frequency will be spaced such distance from the preceding tooth that the pawl will advance idly a certain distance and then engage the tooth and rotate the wheel during the remainder of its stroke, the remaining distance of the stroke of the pawl being the correct amount of rotation of the ratchet wheel and of the movable plates of the condenser. The teeth on the ratchet wheel 8 are arranged in a similar manner to respectively represent and accomplish 10 kilocycle changes in capacity of the condenser.

In those sets where the first graduation of the dial. indicates 550 kilocycles, the first tooth on ratchet wheel 18 will preferably be located so that the pawl 19 during its stroke will engage said tooth at the proper time to cause a 50 kilocycle movement of the condenser in order that the further 100 kilocycle movements shall correspond with the dial on the set.

Since the teeth on each of the ratchet Wheels will be spaced in accordance with the type of condenser used in the various sets 1 do not illustrate any irregular spacing of the teeth on the wheels 8 and 18.

The operation of the electro-magnets 16 and 23 is controlled by the switch mechanism illustrated in Figs. 5 and 6 wherein 35 is a fixed dial having two series of numerals 500 to 1400 inclusive and l to 0 inclusive arranged in concentric circles upon its face. A disk 36 carrying a depending sleeve 30"" is mounted on a revoluble shaft 37 suitably supported on the dial 35. A spring 30" is coiled about the sleeve one end of the spring being secured. to the sleeve and the other end to the dial. A ratchet 37 is secured to the shaft 37 and a pawl 30 mounted'on the disk engages the ratchet. A gear 37" is sccuret to the shaft 87 and meshes with a gear 39" secured to a shaft 39. A two point contact member 40 is secured to the shaft 39 and is adapted to close an electric circuit at the switch points 42, 42. Apertures 38 are formed in the disk each of which exposes one of each of the series of numerals on the dial 35. By inserting the finger in. any aperture 38 the disk may be rotated thereby to the right F i g. until the linger abuts the stop 40. Upon withdrawing the finger the spring 36" retracts the disk, the pawl 30" causing the ratchet 37 and the shaft 37 to retate thereby driving the contact 40 and close the circuit at the switch points 42, 42 as many successive times as the ratchet 37" is advanced by the pawl 36". This dialing switch mechanism is somewhat like he automatic telephone dialing mechanism.

Electric current of suitable power enters through a supply wire 43 that is connected to a switch 44, the wire 45 being connected to the latter switch and to the switch point 4-2. The other switch point 42 is electrically connected to the arm 46 of a selective switch having five contacts bearing the indicia 100, 10, H, L and B respectively. This s witch 4(3 is preferably mounted on a panel P which also supports the dialing mechanism. Another switch 47 is mounted on the panel P and controls the pack in the cabinet, the usual switch 47 on the cabinet also controlling the pack..

A wire 48 leads from the contact R to the electro-magnet 26, the wire 49 leads from the contact 10 to the electro-magnet 16 and the wire 50 leads from the contact 1.00 to the electro-magnet 2?). Upon closing the switches 44 and 47 and moving the switch 45 to the contact 100 the dialing mechanism is then operated to cause the element 4 to swing for securing the particular radio station desired. For example, if the desired station is operating on 1260 kilocycl es, the operators finger is inserted in the eighth aperture 38 above the numeral 1200 on the dial 3a and the disk 86 is rotated. bythe finger to the right (Fig. 5) until the finger meets the stop 40 whereupon the finger is removed successive steps or teeth.

from the disk and the disk retracts causing the contact to close the circuit at the switch points 42, 42 seven successive times. Each time the circuit is closed at the switch points 42,42 the electro-magnet 23 is energized to attract its armature and cause the pawl 19 to rotate the ratchet wheel 18 a distance of one tooth or seven teeth in all when the dial has fully retracted. These movements are transmitted through the shaft 7, the gears 6 and 5' and the shaft 3 to the member 4 which is rotated to the 1200 kilocycle position on the dial of the set. The switch arm 46 is then shifted. to the contact 10 and the finger is inserted in the aperreturn movement of the disk causing the con tact 40 to close thecircuit at the switch points 42, 42 six successive times whereby the electro-magnet 16 is energized and the pawl 10 is caused to rotate the ratchet wheel 8 six The member 4 is thereby caused to rotate to the 1260 kilocycle position. The usual dial on the radio set will indicate the movements just as it does when the usual hand operated member on the cabinet is manipulated.

Any number on the dial of the radio set may be secured in the manner above described. To release the mechanism when a change to any other station is desired the switch arm 46 is moved to the contact R and the disk 36 is rotated to cause the contact 40 to close the circuit at the switch points 42, 42 thereby causing the energization of the electro-magnet 26 and the release of the spring 9. lVhereupon the several parts are restored to normal position by the spring in casing 31, and dialing for the said other station may he proceeded with.

To control the volume of the reception in the radio set I provide two contacts H and L on the switch 46, the contacts being electrically connected by the wires 51, 52 to the solenoid 53, 54 respectively. These solenoids are mounted upon a suitable frame 55 that is positioned in the radio cabinet at a convenient point so that the shaft 56 that is supported on the frame 55 may be connected to the volume control B of the radio set. The armature 57 of the solenoid 53 is suitably connected to a plate 58 that is longitudinally slidably mounted on the frame and the move ment of which toward the solenoid is opposed by the spring 59. A pawl 60 is pivotally mounted on the plate and a spring 61 secured to it and to the plate 58 tends to engage the pawl upon a ratchet wheel 62 that is secured to the shaft 56. A pin 63 projects from the frame and an edge of the pawl bears against the pin. A cam 64 is formed on said edge at a suitable point such that when the plate 58 is retracted to its normal idle posi tion the pin will engage the cam and rock the pawl sufliciently to cause its free end to clear the teeth of the ratchet wheel 62. When the solenoid 53 is energized its armature is drawn inwardly to reciprocate the plate 58 and the pawl 60, which pawl causes the ratchet wheel and shaft 56 to rotate the distance of one tooth on the wheel. By actuating the dial mechanism on the panel l the switch arm 46 being on contact H the amount of rotation of the shaft is controlled. to increase the volume of the reception. To reduce the said volume the switch arm 46 is shifted to the contact L and electric current is supplied to the solenoid 54 under the control of the dialing mechanism in the panel P. The arn'iature 64 of the solenoid 54 is connected to a plate 65 similar to plate 58 and having a pawl 66 pivotally mounted thereon similarly to the pawl 60. The pawl 66 is adapted to eu age the ratchet wheel 67 secured to the slut. 56 and to cause the shaft to rotate in a direction reverse to that caused by the pawl 60. The wihune control B is therefore adjusted by manipulating the dialing mechanism on the panel.

Each of the electric-magnets and solenoids is connected to the other supply circuit wire 43 The panel P may be in any suitable or con venient form so that it may be portable. The several wires leading from the operating devices that are installed in the radio cabinet will preferably be placed in a cable and lead to desirable points in the building containing the radio set, so that the portable set may be connected to the cable at various points.

The radio set may also be operated at the cabinet. To permit such operation it is necessary to provide a suitable clutch C in the shaft 3 which will be thrown out by a suitable lever when hand operation of the set is de sired.

It is now seen that the ratchet wheel 8 is designed to cause the member 4 of the gang condenser 1 to move a distance corresponding to 10 kilocycles on the dial of the radio set for each tooth of said wheel and that the ratchet wheel 18 causes the member 4 to move a distance corresponding to 100 kilocycles on said dial. Hence the frequency on which any broadcasting station is operating which the radio set is adapted to receive may be secured by the remote control mechanism.

hat I claim is:

1. The combination with a radio receiving set having a variable condenser, a tuning dial and a volume control mechanism, of two ratchet wheels to rotate the movable plates of the condenser for tuning the set to any desired frequency within its range, the teeth on each wheel being spaced to correspond with the geometrical spacing of the kilocycle graduations on the tuning dial, electrically actuated members to turn the wheels in the same direction in steps respectively, elecsets provided with a variable condenser, comprising a pair of ratchet Wheels to rotate the plates of the condenser in the same direction, electrically actuated members to cause progressive movement of said'wheels respectively, electrical circuits including the said members respectively, a remote dialing mechanism and means to selectively connect the mechanism to the said circuits whereby to send selected numbers of impulses of elec trical current to the electrically actuated members selectively.

3. The combination with a radio receiving set having a variable condenser, of two ratchet wheels to rotate the plates of the condenser in the same direction, means to retract the said wheels, means to lock the wheels in adjusted position, an electrically actuated member to release said locking means, electrically actuated members to cause progressive movement of said wheels respectively, electrical circuits including said members respectively, a remote dialing mechanism and means to selectively connect the dialing mechanism to said circuits whereby to send selected numbers of impulses to the ratchet Wheel actuating members or to the lock releasing member.

.4. The combination with a radio receiving set having a variable condenser, of two ratchet wheels to rotate the plates of the condenser in the same direction, said teeth on one wheel being spaced to represent 100 kilocycles of movement of the said plates and those on' the other torepresent 10 kilocycles of movement of said plates, electrically actuated members to progressively rotate the wheels respectively, and means to send selected numbers of impulses to the latter members selectively.

5. The combination with a radio receiving set having a variable condenser, of two electrically driven devices to adjust the condenser in progressive l0 and 100 kilocycle movements respectively in the same direction, a dialing mechanism having its scale graduated to represent 10 and 100 kilocycles and a switch to selectively electrically connect the dialing mechanism to the electrically driven devices whereby to send impulses in selected numbers to said devices.

6. Thecombination with a radio receiving set having a variable condenser and a volume control mechanism, of two electrically driven devices to selectively adjust the condenser in progressive 10 and 100 kilocycle movements respectively in one direction only electrically driven devices to operate the volume control mechanism, adialing mechanism and means to selectively electrically connect the dialing mechanism with the electrically driven devices whereby to send impulses of electrical current of selected number to said electrically driven devices.

EDW'ARD H. MERRITT. 

